ML20051S494
| ML20051S494 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 05/03/1982 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20051S493 | List: |
| References | |
| NUDOCS 8205170520 | |
| Download: ML20051S494 (3) | |
Text
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UNITED STATES NUCLEAR REGULATORY COMMISSION E
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j WASHINGTON, D. C. 20555
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 21 TO FACILITY OPERATING LICENSE NO. NPF-7 VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA POWER STATION, UNIT NO. 2 DOCKET NO. 50-339
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Introduction:==
By letters dated February 19, 1982 and March 15, 1982, the Viroinia Electric and Power Company (the licensee) requested a change to Licend indition 2.C.(10) to Facility Operating License No. NPF-7 for the North h.'a Power Station, Unit No. 2 (NA-2).
The licensee's requested change wod defer the completion of the secondary electrical protection for containment penetrations i
from the first to the second refueling outage.
License Condition 2.C.(10) to Facility Operating License NPF-7 (full power) issued August 21, 1980 stipulates:
"No later than October 11,1980, VEPC0 shall submit a design for the backup overcarrent protection system for containment electrical penetrations for Commission review and approval.
The backup system shall be installed and operational prior to resuming power operation following the first refueling outage."
The licensee has already met the provisions of 2.C.(10) regarding the design for the backup overcurrent protection system for contair. ment electrical pene-trations. By letter dated October 10, 1980, the licensee submitted reports for (1) " Electrical Penetration Protection-Power Circuits (Primary and Secondary)"
and (2) " Electrical Penetration Protection Control Circuits (Primary and Sec-7 l
o nda ry)."
Our letter to the licensee dated November 10, 1980 stated that the NA-2 elec-trical fault protection for containment penetrations was in accordance with our requirements as specified in regulatory position C.1 of Regulatory Guide 1.62, Revision 2, " Electrical Penetration Assembles in Containment Structures for light Water Cooled Nuclear Power Plants." The basis for our conclusione, was so stated in the enclosed Safety Evaluation to our letter.
The licensee's letter of February 19, 1982 stated that the present ten week first refueling outage for NA-2 has become impacted with the extensive time required for installing and testing circuits.
In addition, other NRC require-ments, all of which must be completed within the confined physical constraints
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of the NA-2 electrical penetration area and during the first refueling outage, have further impacted completion of required work. Therefore, the licensce has requested that the required implementation date for License Condition 2.C.(10) be extended from the first to the second NA-2 refueling outage.
820517090
4 ' Our discussion and evaltation of the licensee's above request is presented below:
1 Discussion:
The licensee has stated that nine power circuits do not require secondary protection because the circuits are deenergized during Operating Modes 1 l
2, 3 and 4 when containment integrity is required. Also an additional 38 control circuits already have adequate protection, and have been reviewed by the NRC staff and found acceptable.
The licensee has determined that the installation and testing time required for the remaining 293 circuits is approximately 25 weeks. The extensive time required is due in part to the quantity of circuits requiring modi-fication and testing and the physical constraints of working in he electrical penetration area. Also, other required modifications in this confined area for the first refueling outage include NUREG-0737 Action Items for a Reactor Vessel Level Indication System, Post Accident Sampling System, and Reactor Vessel Head and Pressurizer Vent System.
In addition, work in this area is further impacted by required periodic testing at electrical penetrations and emergency buses specified in the NA-2 Technical Specifications (TS).
Therefore, the licensee has stated that on an approximate basis, thirty (30) percent (88 circuits) will be completed during the first refueling outage; five (5) percent (14 circuits) during the fall 1982 maintenance outage; an additional thirty (30) percent 88 circuits) during cycle 2 power operations; and the final thirty-five (35)(percent (103 circuits) completed during the second refueling outage in the spring of 1983.
Evaluation:
Based on the low probability of a Loss-of-Coolant Accident (LOCA) and an electrical penetration fault developing between first and second refueling outages which could threaten the mechanical integrity of an electrical penetration concurrent with failure of the protection device to interrupt the fault, deferment for the completion of the secondary protection of containment electrical penetrations to the second refueling outage is acceptable.
Installation of approximately thirty percent of the secondary protective devices during the first refueling outage and the additional five and thirty percent during the fall 1982 maintenance outage and cycle 2 power operations will provide added assurance with regard to integrity during this period.
l In regard to the nine circuits which are normally deenergized, we require that a limiting condition of operation (LCO) be provided in the NA-2 TS to require that these circuits be maintained deenergized durin9 all oper-ating modes except cold shutdown and refueling.
l By letter dated March 15, 1982 the licensee submitted a TS change request which complies with our requirements. This item is therefore resolved.
l
. E Based on the above, we conclude that the licensee has complied with the i
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stipulations of License Condition 2.C.(10) to the extent practicable at l
this time and has shown good cause for requesting relief from the imple-l mentation clause of License Condition 2.C.(10),
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We further conclude that for the period of time for which relief is granted, implementation will continue on an ongoing basis and thus provide additional assurance regarding secondary protection for the NA-2 containment electrical penetrations.
Therefore, License Condition 2.C.(10) is hereby revised to state that the completion date for the backup overcurrent protection system shall be in-stalled and operational prior to resuming power operations following the second refueling outage.
Finally the NA-2 TS are hereby revised to specify a LC0 on the d a deenergized powercIrcuits.
Environmental Consideration We have detennined that the amendment does not authorize a change in effluent types or total amounts nor an increase in power level and will not result in any significant environmental impact. Having made this determination, we have further concluded that the amendment involves an action which is insignificart from the standpoint of environmental impact and, pursuant to 10 CFR $51.5,(d)(4), that an environmental impact statement or negative declaration and environ-mental impact appraisal need not be prepared in connection with the issuance of this amendment.
l l
Conclusion We have concluded, based on the considerations discussed above, that:
(1) because the amendment does not involve a significant increase in the probability or consequences of accidents previously considered and does not involve a significant decrease in a safety margin, the amendment does not involve a significant hazards consideration, (2) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, and (3) such activities will be conducted in compliance with the Commission's regulations and the issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public.
1.
Date: May 3, 1982 Principal Contributors:
J. Lazevnick L. B. Engle
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